Pneumatic transmission system.



F. B. D'HUMY.

PNEUMATIG TRANSMISSION SYSTEM.

APPLICATION I'ILBD MAR.25. 1912. l 1,092,982. Patented A111114, 1914.

2 SHIETS-SHBET 1.

P. E. DHUMY.

PNEUMATIG TRANSMISSION SYSTEM.

APPLICATION FILED 111111.25-, 1912.

1,092,982. Patented 111111111914.

2 SHEETS-SHEBT 2.

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FERNAND E. DIIUMY, OF ENGLEWOOD, NEW JERSEY, ASSIGNOR TO TI-IE WESTERN UNION TELEGRAPH COMPANY,

A CORPORATION 0F NEW YORK.

PNEUMATIC TRANSMISSION SYSTEM.

To all whom it may concern Be it known that I, FERNAND E. DHUMY, a citizen of the United States, and a resident of Englewood, county of Bergen, and State of New Jersey, have invented certain new and useful Improvements in Pneumatic Transmission Systems, of which the following is a specification.

This invention relates to pneumatic transmission systems of a class to be herein known as exhaust systems or systems of the eX- haust type.

Pneumatic transmission systems may be divided into three general classes. In Athe first class the carrier is despatched through the tube by a propelling blast of air pumped into the sending side of the tube circuit. In the second class the carrier is despatched through the tube by exhausting the air at a pumping station from the return side of the tube circuit, The third class combines the characteristics of both of the other classes, the carrier being despatched through the tube by exhausting air from the return side of the tube circuit and also by a propelling` air blast injected into the sending side of the tube circuit. The last two classes of such systems may be designated as systems of the exhaust type since transmission of the carrier is effected in whole or in part by eX- hausting air from the return side of the tube circuit.

The present invention has reference to the terminal at the receiving station.

One feature relates to an arrangement for providing an air cushion stop in the terminal for the carrier combined with a relief valve controlled by the attendant and adapted to admit atmospheric pressure to the terminal for the discharge of the carrier. Each carrier upon its arrival is regularly brought to a complete stop in the` terminal by the air cushion stop and there remains until it is discharged at the will of the attendant by the opening of the relief valve.

Another feature of the invention relates to the provision of a signal to indicate the arrival of the carrier at the receiving station.

Another feature of the invention relates to a novel arrangement in a double valve terminal, which is simple and reliable in operation, for restablishing the vacuum in the terminal or pocket after the vacuum has Specification of Letters Patent.

Application led March 25, 1912.

Patented Apr. 14, 1914. serial No. 685,908.

been broken to facilitate the discharge of the carrier from the terminal.

In the accompanying drawings forming part of this specification, and in which like reference numerals designate corresponding parts in the several figures, the invention is shown in its preferred form in Figures 1, 2, and 8 and in a modilied form in Figs. 4, 5

'and 6. Fig. 1 is a vertical sectional elevation of the invention in its preferred form. Fig. 2 is 4an elevation looking in the direction of the arrow 2 of Fig. 1. Fig. 3 is a sectional plan view on the line 3 3 of Fig. 1. Fig. 4 is a view similar to Fig. 1 showing a modification. ing in the direction of the arrow 5 of Fig. 4. Fig. 6 is a sectional plan view on the line (nl-6 of Fig. 4.

Referring now to the particular features shown in Figs. 1, 2 and 3 of the drawings, 1 is the main tube or passage-way of the system having an elbow 2. 3 is a downwardly directed tube leading from the main tube at the elbow and communicating with a receiving pocket 4. Between the tube 3 and receiving pocket 4 is a valve casing 5 provided with a check valve 6 having a valve seat 7 and adapted when closed to cut olf communication between the main tube and the receiving pocket. As shown, this valve consists of a leather or other flexible disk sufficiently weighted to open the valve when the air pressure in the valve casing on both sides of the valve is substantially equal, it being preferable to arrange this valve so as to be normally open and to be closed by air pressure when the relief valve is opened. The pocket 4 is provided at its lower end with a discharge opening 8 for the carrier. This opening is providedv with a closure which is preferably in the form of a selfclosing valve 9. This valve is pivoted on a bracket 10 and is provided with a counterweight 11 so that the valve acts to close itself when not prevented from so doing. 12 is a tube or passage-way secured to the valve casing 5 and communicating with the receiving pocket 4 forward of the valve 6. The lower end of the tube 12 rests upon and is closed by a bracket 13. The tube 12 is provided with peripheral slots 14 arranged to be closed by the relief valve 15 compris ing a rotatable sleeve having peripheral slots 16 and handle 17. By means of this valve Fig. 5 is an elevation looky 15 air pressure from a suitable source preferably outside air may be admitted to or cut of from the tub-e 12.

The parts are shown in their normal position in Figs. 1, 2 and 3 in which position the valve 6- is open and valves 9 and 15 are closed, a partial vacuum being maintained in the main tube, in the receiving pocket and the tube 12. As is usual in such systems, the carrier closely tits the main tube. It also closely tits the tube 3, the valve casing 5 and receiving pocket 4. Then the carrier arrives by way of the main tube, it-*passes through the tube 3, the valve casing 5 and into the receiving pocket 4, wherein it crowds the air in front of it against the valve 9 to form an air-cushion stop for the carrier. The attendant then opens the relief valve 15 to admit outside air, the pressure of which immediately closes the valve G and cuts off communication between the receiving pocket and the main tube. At the same time the pressure of the outside airis admitted to the receiving pocket 4 behind the carrier or behind the stopping vplace for the carrier so that the carrier thereupon presses open the valve 9 and drops out of the pocket. lhen the carrier has passed out, the valve 9'closes itself owing to its counter-weight `11. The attendant then closes the valve 15 whereupon the air in receiving pocket 4 and tube l2 is drawn out through the elbow 2 and the main tube 1, leaking' past the valve G which, although closed, is arranged to admit of such leakage. When the air pressure in the pocket 4 and the tube 12 have been so reduced as to establish substantially7 equal pressure on both sides of the valve 6, this valve may drop to open position thereby bringing t-he parts into their' normal state, as shown in Fig. 1.

The employment of a relief valve whose opening is controlled by the attendant, in-` stead of the employment of a valve opened automatically by each carrier upon its arrival in the terminal, is an important feature. This arrangement enables one or more carriers to closely follow the first carrier into the terminal and to be discharged together and at one opening of the relief valve. Thus, it would not be necessary to delay the despatch of a. carrier until the one preceding it had ample time to enter and be discharged from the terminal. Where a relief valve is employed which is opened automatically by each carrier such carrier must be discharged from the terminal and the parts restored to normal condition, including the restoration of the vacuum in the terminal, before a second carrier arrives in the terminal or reaches the check'valve between the terminal and the main tube. The number of carriers which could be despatched without time allowancel from the sending station, between the carriers, or

which could simultaneously occupy the terminal at the same time, where the opening of the relief valve is controlled by the at- Y tendant, is merely dependent upon the length of the terminal below t-he check valve. In the accompanying drawings, the terminal is shown as being of a length and suiiicient to contain several carriers at the same time. A second carrier following closely the preceding carrier into the terminal would form its own air cushion stop in the terminal immediately in advance of itself and behind the preceding carrier, just as the first carrier forms its own air cushion stop in advance of itself.

lt will be seen that in the arrangement described, the carrier is brought to rest and discharged without shock to the parts and without noise incident to an inrush or outrush of air which usually characterizes other pneumatic transmission systems and is objectionable.

Referring now to the signaling device, 18 is a signal lamp which may be located at any convenient po-int but, as shown in the drawings, is fixed to the under side of the bracket 13 near the discharge opening of the pocket 4. The lamp is arranged in a circuit 19 which includes thegenerator 20 and the coils of amagnet 21 having a fixed contact 22 and a movable contact 23 carried by the armature 24. The contacts 22 and 23 are included in the lamp circuit and are normally open. lhen these contacts are closed, the lamp circuit is closed and the lamp is illuminated. Contacts 22 and23 are controlled by the air pressure in the pocket 4', being open when such air )ressure isat its normally reduced state anc closing upon the increase of pressure due to the formation of the air-cushion produced by the arrival of the carrier. Thus, when the carrier arrives, its air-cushion stop closes contacts 22 and 23 and illuminates lamp 18. When once these contacts have been closed, they are held closed by magnet 21 until the lamp circuit has been broken. The control ofr contacts 22 and 23 by the air pressure in the pocket 4 is effected, in the present instance, by providing a port 25 near the lower end of the receiving pocket and the valve 26 therefor which carries a rod 27 designed to push against the armature 24 to close these contacts. This valve 26 is carried on the arm 2S pivoted to a bracket 29 and the rod 27 is disconnected from the armature 24 so that the valve 2G may close while the armature 24 is still attracted by the magnet. The valve 26, port 25 and magnet 21 are inclosed in a chamber 30 having a removable cover 31.

32 is a tube having a coupling 33 which connects the chamber 30 with the pocket 4 behind the stopping place of the carrier. Thepurp'ose of thischamber and tube to iso equalize the pressure on both sides of Ithe valve 26 after the valve 9` has been closed subsequent to the discharge of the carrier, so that the valve 26 may operate. This valve zuitomatically closes as soon as the carrier has been disch-arged.

34 and 35 are contacts in the lamp circuit cont-rolled by the relief valve 15. When this valve is closed, the contacts are closed and when the valve is opened to discharge the carrier7 these contacts are opened to extinguish the lamp.

Although it is preferred to employ a handoperated relief valve, one form of which is shown in F igs.` l, 2 and 3, the invention contemplates an automatically operated relief valve, as well. One arrangement of such automatically operated relief valve is shown in Figs. 4, 5 and G. As there shown, the lower end of the tube l2 is provided with a horizontally slotted fiat plate 36 having a similarly slotted valve plate 37 arranged to reciprocate in two vertical guides 38. To the lower end of this valve plate 37 is attached a piston rod 39 and piston 40 working in a piston chamber 4l. The port 42 opens into the piston chamber from near the lower end of receiving pocket 4. 43 is a tube having a similar function and purpose to that of tube 32 of Fig. l.

When the carrier arrives in the pocket 4, as shown in Fig. 4, the accumulating air pressure of the air-cushion passes through the port 42 underneath the piston 40, therel by lifting this piston and opening valve 37,

whereupon the carrier pushes open the valve 9 and drops out of the pocket. The piston 40 is so weighted that it does not operate in response to the pressure of the air-cushion until the carrier has been arrested. After the carrier has been discharged and the presJ` sure in the piston chamber above and below the piston 40 has been equalized, piston 40 drops to its lower position and closes valve 37.

A different arrangement of signal iS shown in Figs. 4, 5 and 6. As here shown, the lamp 44 is lixed in alinement with glass disks 45 and 4G which cover alined openings in the walls of the pocket 4. The lamp 44 is permanently illuntfinated and its light is visible to the attendant at the glass disk 46 which is preferably ground to disperse the light rays. When there is no carrier in the pocket, the light is visible but when the carrier arrives at the pocket, it cuts oil' the light from the lamp and thereby indicates the presence of the carrier.

lhat is claimed and what is desired to be secured by Letters Patent is l. In a pneumatic transmission system of the exhaust type, the combination of a main tube; a receiving pocket connecting with the main tube and normally containing substantially the same working pressure as the main tube and designed to closely fit t-he carrier to provide for forming in said pocket an air cushion stop designed and adapted to bring the carrier to a complete stop within the pocket, said pocket having a valved discha rgc opening for the carrier; a check valve between the pocket and the main tube; and a valve controlled by the attendant for opening the pocket to atmospheric pressure to discharge the carrier.

' 2. In a pneumatic transmission system of the exhaust type, the combination of a main tube; a receiving pocket connect-ing with the main tube and normally containing substantially the same working pressure as the main tube and designed to closely fit the carrier to provide for forming in said pocket an air cushion stop within the pocket, said pocket having' a valved discharge opening for the carrier; a check valve between the pocket and the main tube, said valve having provisions for leakage therethrough in closed posit-ion to equalize the pressure on both sides of the valve; and a valve controlled by the attendant for opening the pocket to atmospheric pressure to discharge the carrier.

3. In a pneumatic transmission system, the combination of a main tube; a receiving pocket connecting with the main tube and designed to closely lit the carrier to provide for forming in said pocket an air-cushion stop for the carrier; a relief valve to admit pressure behind the stopping place of the carrier; and a signal to denote the arrival of the carrier controlled by the air pressure in said pocket and by said relief valve.

4. In a pneumatic transmission system, the combination of a main tube; a receiving pocket connecting with the main tube and designed to closely fit the carrier to provide for forming in said pocket an aircushion stop for the carrier; a signal circuit and signal to denote the arrival of the carrier; and a circuit closer in said circuit controlled by the air pressure in the receiving pocket.

5. In a pneumatic transmission system, the combination of a main tube; a receiving pocket connecting with the main tube and designed to closely tit the carrier to provide for forming in said pocket an ail-cushion stop for the carrier; a signal circuit and signal to denote the arrival of the carrier; a circuit closer in said circuit; and a valve controlling a port near the outer end of the receiving pocket and also controlling said circuit closer.

G. In a pneumatic transmission system, the combination of a main tube; a receiving pocket connecting with the main tube and designed to closely lit the carrier to provide for forming in said pocket an air-cushion stop for the carrier; a relief valve to admit pressure behind the stopping place of the carrier; and a signal to denote the arrival of the carrier and provisions for causing the lll@ signal to be displayed operable upon the arrival of the carrier in Said pocket, the witlidi'awal of the signal being` controlled by the relief valve.

'7. In :i pneumatic transmission Systenni the combination of zi main tube; zi receiving pocket connecting with the infini tube and designed to closely fit the carrier to provide for forming in said pocket :in nir-cushion r stop foi' the carrier; i relief valve to admit l pressure behind the stopping place of the carrier; a. signal circuit and signal to denote In testimony whereof, I have signed my nume to this specification, inthe presence of two subscribing witnesses.

FERNAND E. ifHUMY.

itnesses z v H. IV. MoREHoUsE, IDA G. GILMORE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

